The present invention pertains to feeding individual sheets seriatim, as part of the processing of a mailing system, and more particularly to feeding sheets to an accumulator from which the sheets can be directed on to various paths in the mailing system.
Various accumulator apparatuses and methods have been employed in the prior art for accumulating sheet materials or articles such as paper sheets, documents, and the like into stacks for subsequent advancement. Such accumulator systems are used in particular in high-speed mail processing, where preparing and processing mailable articles often requires a set of sheet articles (a collation) to be assembled into a stack (packet) for further handling, which can include folding, inserting, and collating.
It is essential in a high-speed mailing system that processing paths be arranged to pose as low a risk as is feasible of a sheet causing a jam. To arrive at a design for processing sheets, a combination of tradeoffs are made. In one approach to designing an accumulator that is especially unlikely to cause a sheet to jam, the accumulator might be specialized to particular size sheets or to sheets with particular bending properties (relevant for folding the sheets). In such a design, it is advantageous to provide for selectively diverting some sheets in case they are different from the kind intended for a normal processing path.
Even if a jam does not occur, however, it is sometimes necessary to divert sheets from the normal processing path, such as in case where a sheet has been mis-scanned by a bar code reader because, for example, the bar code is not clearly inscribed.
Thus, what is needed is a system for accumulating sheets in a manner that poses an especially low risk of any problem in processing at least some kinds of sheets, and that conveys a stack of accumulated sheets along either a normal processing path or an alternative processing path, and that also provides for diverting sheets in case of a problem with the sheets.
Accordingly, the present invention provides a system for accumulating sheets as part of the operation of a mailing system and for conveying the sheets along a normal feed path, the system including: a sheet feeder for feeding sheets seriatim; a bar code reader, responsive to bar code indicia on the sheets, for providing a bar code scanned signal; a receiving bin for receiving and stacking the sheets in a bin receptacle; a registration and jogging module for stopping the sheets over the receiving bin so that they fall properly into the bin receptacle, and further for edge-aligning the sheets in the bin receptacle, and still further for ejecting sheets out of the receiving bin along the normal feed path; a mis-scan controller, responsive to the bar code scanned signal, for providing mis-scan diverter commands for sheets that have been mis-scanned; a mis-scan diverter, coupled to the receiving bin, responsive to the mis-scan diverter commands, for diverting those sheets that have been mis-scanned from the normal feed path to a first alternate path; a selective controller, responsive to the bar code scanned signal, for providing selective diverter commands for diverting sheets selectively; and a selective diverter, coupled to the receiving bin, responsive to the selective diverter commands, for diverting selective document sets from the normal feed path to a second alternate path.
In a further aspect of the invention, the receiving bin of the accumulator includes: a free running idler roller mounted on a low-angle ramp that rises toward a continuously running belt, the free-running idler mounted at the end of the low-angle ramp closest to the continuously running belt, and disposed so as to form a nip with the continuously running belt, thereby arranging that sheets are provided to the receiving bin in a substantially planar feed path.
In another, further aspect of the invention, the registration and jogging module includes: a pusher assembly including a stepper motor for back and forth jogging of the sheets accumulating in the receiving bin, and two rollers driven by the stepper motor via a timing belt, and also including at least one pusher member located on the timing belt; and a stop assembly including a stepper motor for back and forth jogging, and two rollers driven by the stepper motor via the timing belt, and also including at least one stop member affixed to the timing belt and disposed so that as sheets are fed into the receiving bin 1a they strike the stop member and fall into the bin receptacle where they are then jogged and edge-aligned.
In yet another, further aspect of the invention, the selective diverter includes a pivot table by-pass guide positioned according to commands received from a selective controller so as to selectively divert a sheet. In such an embodiment, a nip is formed at the distal end of the pivot table by-pass guide by a continuously running cooperating roller and a surface of the pivot table by-pass guide, so that a sheet entering the nip so formed is diverted to the second alternate path.
In yet even another, further aspect of the invention, the mis-scan diverter includes a diverting chute assembly that is made to rise up into the feed path so that a sheet enters the diverting chute assembly and is thereby provided to the first alternate path, the diverting chute assembly being raised and lowered under the command of a mis-scan controller.